1. Statement of the Technical Field
The present invention relates to the edge processing of Web content and more particularly to edge processing dynamically generated Web content.
2. Description of the Related Art
As business organizations deploy important business applications over the Internet, challenges arise in the form of processing delays and network latencies. Specifically, the placement of application content in a centralized server can compel users' requests to traverse multiple congested networks in an attempt to effectively interact with the application. In consequence, this centralized approach to deploying applications on the Internet can hinder the attainment of scalability, reliability and performance levels that are considered “mission-critical” in the deployment of a business application.
In view of these challenges, and further in view of the business importance of delivering requested content to end users as quickly as possible, the general problem of reducing response time has received significant attention recently. Most proposed solutions have focused upon accelerating the delivery of static content through distributed caching. An example of such distributed caching includes the Web Sphere™ Edge Server™ manufactured by International Business Machines Corporation of Armonk, N.Y. Other proposed solutions involve the use of a content distribution network (CDN) such as the CDN deployed by Akamai Technologies of Cambridge, Mass.
The use of optimized delivery mechanisms for static content has become less significant in recent years, however, as content distributed over the Internet has become increasingly “personalized.” More particularly, in order to attract and retain “eye-balls”, businesses include within their on-line applications, content which is dynamically tailored to particular end-users. As a result, because this type of content can vary from user to user, this type of content cannot easily be cached. Hence, the latencies previously associated with the challenges of static content remain a problem for dynamically generated content.
Technologies intended to improve the delivery of dynamic content over the Internet have begun to emerge. As an example, International Business Machines Corporation now includes an “application off-load” feature in the Edge Server™ product. The application off-load feature extends the WebSphere™ platform to the edge of the network, enabling unprecedented availability, scalability, and performance for sophisticated e business applications.
By comparison, Ejasent, Inc. of Mountain View, Calif. provides the UpScale™ service which targets customers who have “lumpy” amounts of Web traffic. Specifically, the UpScale service involves first copying an entire application stack, associated data and content for a Web site into a single file. Once the single file has been created, the file can be uploaded to a hub. The hub, in turn, can distribute the single file to various servers at the edge of the network close to the end-user (edge servers). Upon receiving a user request, a participating server can load the application from the single file for processing without requiring the request to be processed centrally in a central application server (origin server).
Notably, as will be apparent to one skilled in the art, both the Edge Server and UpScale products encourage developers to create applications as components which then may be vertically distributed. Components are “deployed” a priori to distributed computers via an out-of-band mechanism. In contrast, the emerging Edge Side Includes (ESI) technology, addresses dynamic content all the while remaining flexible in that ESI does not require a priori deployment of application components. Rather, ESI technology enables the distributed assembly of Web pages from templates and fragments.
Using ESI, an edge server close to an end user fields a page request, forwarding to an origin server only the requests for individual fragments of data that require processing or updating. These individual data fragments are then returned to the local edge server, where the fragments are re-assembled alongside cached and unexpired updateable elements. Subsequently, a Web page can be generated. In consequence, much of the burden of processing and generating an entire application page or Web page is lifted from the origin server while the final generation of the page can be performed in the edge server. Still, despite the flexibility of ESI technology, ESI technology remains a fixed function solution. As a result, the entire infrastructure must be modified in order to introduce new functionality.